The goal of the Clinical Core is to facilitate high quality clinical, neuropsychological, epidemiological and neuropathological research regarding Alzheimer's disease. Three considerations influenced the design of the proposed Core: the expertise of investigators at Rush, the establishment of a Memory Assessment Clinic at Cook County Hospital, and the success of the Religious Orders Study Core. These considerations led to a design that will recruit and follow very large numbers of cases and controls for clinical studies but a relatively small group for neuropathologic studies, and will emphasize enrollment of African American and Hispanic minorities. The Core proposes to perform uniform structured baseline evaluations and follow 1,750 persons with dementia who agree to a brief annual informant interview, 150 persons who agree to a detailed annual clinical evaluation and brain donation at death, and 250 controls who agree to an annual interview. This approach will provide investigators using Core resources a large pool of subjects who are potentially eligible for externally funded studies. This approach will allow the Clinical Core to continue to build on its record of success. During the past project period, more than 1,600 persons enrolled in the Core. Follow-up interviews were performed on more than 85%. Almost 500 persons participated in one or more of 14 externally funded clinical projects. In addition, the overall autopsy rate in the Core exceeds 80% (265 autopsies of 322 deaths). Brain tissue from almost 150 persons were used in externally funded studies. Core personnel facilitated 22 other funded projects. While minority enrollment in the Core and in studies using subjects from the Core are both in excess of 15%, the Memory Assessment Clinic at Cook County should greatly facilitate enrollment of additional minorities.